T(2n-1,n-2), T given by A026714.

Terms

a(0) =1a(1) =8a(2) =49a(3) =276a(4) =1503a(5) =8059a(6) =42879a(7) =227209a(8) =1201198a(9) =6342065a(10) =33458422a(11) =176429692a(12) =930053109a(13) =4901862563a(14) =25832186354a(15) =136121375543a(16) =717246503129